This investigation will examine patterns of cancer staging at diagnosis, treatment, and survival in the elderly population of the state of New Mexico. The overall goal is to identify remediable deficiencies in the sequence leading from onset of cancer symptoms to diagnosis and treatment by the health care system. The proposed investigation has three components. The first involves a comprehensive analysis of data already collected by the New Mexico Tumor Registry (NMTR), a population-based cancer registry which participates in the NCI's Surveillance, Epidemiology, and End Results (SEER) Program. Analysis, directed primarily at the effects of age on stage at diagnosis, treatment, and survival, will involve approximately 40,000 cases diagnosed among all New Mexico residents and American Indians in Arizona, 1969-1982. In the second component, interviews will be conducted with residents of the Albuquerque-Santa Fe area who are newly diagnosed with cancer and at least 65 years of age. The population-based case series will be ascertained through the NMTR during the first two years and will include approximately 800 subjects. The interviews to be conducted with index subjects and the spouse or other key person, will obtain information related to delay, availability and use of medical care, social support system, activity level, mental status, recent major life events, and psychological status. The relationships between these factors and stage at diagnosis, and intensity of treatment will be assessed. The third component will evaluate physician treatment of cancer in the elderly. Using NMTR data for specific sites, we will describe variation among physicians in the intensity of cancer treatment. We will also administer a questionnaire concerned with knowledge and attitudes about the aging process to certain active physicians and correlate responses with actual practice, as documented by the NMTR. Each of the separate, population-based components should provide results relevant to cancer control in the elderly.